Im going to start with simple and move on.
The best easy option is freedompop.com. They sell a 4g hotspot for 30 bucks. They give you 500 megs free then charge about 10 bucks a gig after that. You don't wind up on a contract paying for service you only use when on the road. I would start with this.
For TV. I would look at dish the setup is around $400 you might be able to get the equipment used on ebay much cheaper. The tech has not changed for a while. What you might want to look at is either pay as you go or set your home up on the service you wind up using in the RV that way there is no extra cost after equipment purchase. Dish also has a turn on and turn off service but that sounds like a pain if you are shooting off for a weekend.
Now for the cell phone. Its time to get a big boy phone. I am an apple fan but there is plenty of good in the android world. You need something with 4g or a phone that can hook up to as many networks as possible (the new iphones can go to any carrier) GPS maps and all that are invaluable. Plus the phone becomes your email box and goto camera. A setup like that can make wanting in RV internet not as big a deal and you can always laptop at McDonalds or Starbucks (by the way starbucks is google gig ethernet very fast) I think this is a big deal if anything just for safety.
If you plan to go where no man has gone before. Don't be cheap buy a satallite phone or rent when you are going somewhere nuts. Most will think its over kill but if you have a medical emergency and mechanical emergency at the same time 20 miles from service. Your dead. You can also get get a spot satellite messenger for 150 bucks plus service http://www.amazon.com/SPOT-Satellite...ocator+beacons
And have the paramedics in a helicopter in seconds. I wont go back packing without one.